I. Field
The present disclosure relates generally to wireless communications, and more specifically to techniques for managing resource assignments in a multi-carrier wireless communication environment.
II. Background
Wireless communication systems are widely deployed to provide various communication services; for instance, voice, video, packet data, broadcast, and messaging services can be provided via such wireless communication systems. These systems can be multiple-access systems that are capable of supporting communication for multiple terminals by sharing available system resources. Examples of such multiple-access systems include Code Division Multiple Access (CDMA) systems, Time Division Multiple Access (TDMA) systems, Frequency Division Multiple Access (FDMA) systems, and Orthogonal Frequency Division Multiple Access (OFDMA) systems.
Generally, a wireless multiple-access communication system can simultaneously support communication for multiple wireless terminals. In such a system, each terminal can communicate with one or more base stations via transmissions on the forward and reverse links. The forward link (or downlink) refers to the communication link from the base stations to the terminals, and the reverse link (or uplink) refers to the communication link from the terminals to the base stations. This communication link can be established via a single-in-single-out (SISO), multiple-in-signal-out (MISO), or a multiple-in-multiple-out (MIMO) system.
A MIMO system can support time division duplex (TDD) and frequency division duplex (FDD) systems. In a TDD system, forward and reverse link transmissions can be made on a shared frequency region so that the reciprocity principle can be used to enable estimation of a forward link channel separate from a reverse link channel. In turn, this can enable an access point to implement transmit beamforming gain on the forward link when multiple antennas are available at the access point.
Further, for various TDD systems utilizing orthogonal frequency division multiplexing (OFDM), a plurality of downlink subframes can generally be associated with one or more uplink subframes for feedback communication. A group of downlink subframes assigned to fewer uplink subframes for feedback communication is conventionally referred to as a bundling window. Thus, a device receiving transmissions on resources within a bundling window can perform feedback operations on the designated uplink subframe(s) for the bundling window. One type of feedback mode for TDD systems is acknowledgment (ACK)/negative acknowledgment (NACK) messaging, in which case a grouping of downlink subframes can be referred to as an ACK/NACK bundling window. Downlink transmissions received by the UE within this ACK/NACK bundling window are acknowledged on the uplink subframe(s). This bundling window design for wireless signals can result in more efficient utilization of downlink and uplink signal resources, providing an overall improvement for wireless communication systems.
In view of at least the above, it would be desirable to implement techniques by which bundling windows can be assigned, managed, and/or utilized in a multi-carrier wireless communication environment in a substantially efficient manner.